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Background: An important goal of providing amplification to children with hearing loss is to ensure that hearing aids are adjusted to match targets of prescriptive procedures as closely as possible. The Desired Sensation Level (DSL) v5 and the National Acoustic Laboratories' prescription for nonlinear hearing aids, version 1 (NAL-NL1) procedures are widely used in fitting hearing aids to children. Little is known about hearing aid fitting outcomes for children with severe or profound hearing loss., Purpose: The purpose of this study was to investigate the prescribed and measured gain of hearing aids fit according to the NAL-NL1 and the DSL v5 procedure for children with moderately severe to profound hearing loss; and to examine the impact of choice of prescription on predicted speech intelligibility and loudness., Research Design: Participants were fit with Phonak Naida V SP hearing aids according to the NAL-NL1 and DSL v5 procedures. The Speech Intelligibility Index (SII) and estimated loudness were calculated using published models., Study Sample: The sample consisted of 16 children (30 ears) aged between 7 and 17 yr old., Data Collection and Analysis: The measured hearing aid gains were compared with the prescribed gains at 50 (low), 65 (medium), and 80 dB SPL (high) input levels. The goodness of fit-to-targets was quantified by calculating the average root-mean-square (RMS) error of the measured gain compared with prescriptive gain targets for 0.5, 1, 2, and 4 kHz. The significance of difference between prescriptions for hearing aid gains, SII, and loudness was examined by performing analyses of variance. Correlation analyses were used to examine the relationship between measures., Results: The DSL v5 prescribed significantly higher overall gain than the NAL-NL1 procedure for the same audiograms. For low and medium input levels, the hearing aids of all children fit with NAL-NL1 were within 5 dB RMS of prescribed targets, but 33% (10 ears) deviated from the DSL v5 targets by more than 5 dB RMS on average. For high input level, the hearing aid fittings of 60% and 43% of ears deviated by more than 5 dB RMS from targets of NAL-NL1 and DSL v5, respectively. Greater deviations from targets were associated with more severe hearing loss. On average, the SII was higher for DSL v5 than for NAL-NL1 at low input level. No significant difference in SII was found between prescriptions at medium or high input level, despite greater loudness for DSL v5 than for NAL-NL1., Conclusions: Although targets between 0.25 and 2 kHz were well matched for both prescriptions in commercial hearing aids, gain targets at 4 kHz were matched for NAL-NL1 only. Although the two prescriptions differ markedly in estimated loudness, they resulted in comparable predicted speech intelligibility for medium and high input levels., (American Academy of Audiology.)

Objective: The study aims to compare the performance of hearing aids fitted according to the NAL-NL1 and DSL v5 prescriptive procedure for children., Design: This is a crossover four period trial., Study Sample: Sixteen school-aged children with moderately severe to profound hearing losses participated in the study. The children were fitted with Phonak Naida V SP hearing aids according to the two prescriptive procedures., Results: The results showed that children performed significantly better with DSL v5 than with NAL-NL1 prescription for sentence perception in quiet. The paired-comparison judgments of speech intelligibility showed seven children significantly preferred the DSL v5 prescription while two children preferred the NAL-NL1 prescription. The average scores on functional and ratings by parents and teachers performance of children in real life were significantly better for the DSL v5 prescription. At the end of all trials, nine children preferred the DSL v5 prescription, four preferred the NAL-NL1 prescription, and two had no preference., Conclusions: Hearing aids fitted based on the DSL v5 procedure would seem to be more appropriate than the NAL-NL1 procedure for children with moderately severe to profound sensorineural hearing loss, at least in quiet listening environments.

Background: Hearing loss is a common sensory impairment experienced by older persons. Evidence shows that the use of hearing aids and/or assistive listening devices (ALDs) can benefit those with a hearing loss but that historically the uptake and use of these technologies has remained relatively low compared with the number of people who report a hearing loss., Purpose: The aim of this study was to determine the prevalence, usage, and factors associated with the use of hearing aids and ALDs in an older representative Australian population., Research Design: A population-based survey., Study Sample: A total of 2956 persons out of 3914 eligible people between the ages of 49 and 99 yr (mean age 67.4 yr), living in the Blue Mountains, west of Sydney, completed a hearing study conducted from 1997 to 2003., Data Collection and Analysis: Hearing levels were assessed using pure tone audiometry, and subjects were administered a comprehensive hearing survey by audiologists, which included questions about hearing aid and ALD usage. Logistic regression analysis was used to identify factors associated with hearing aid and ALD usage., Results: Of the surveyed population, 33% had a hearing loss as measured in the better ear. 4.4% had used an ALD in the past 12 mo, and 11% owned a hearing aid. Of current hearing aid owners, 24% never used their aids. ALD and hearing aid usage were found to be associated with increasing age, hearing loss, and self-perceived hearing disability., Conclusions: These results indicate that hearing aid ownership and ALD usage remains low in the older population. Given the significant proportion of older people who self-report and have a measured hearing loss, it is possible that more could be helped through the increased use of hearing aid and/or ALD technology. Greater efforts are needed to promote the benefits of these technologies and to support their use among older people with hearing loss., (American Academy of Audiology.)

Background: Hearing fluctuation imposes the biggest challenge in the fitting of hearing aids for patients with Ménière's syndrome., Purpose: This study shows that the problem maybe be overcome by allowing the patients to test their own hearing and to program their own hearing aids to adjust for hearing fluctuation. RESEARCH DESIGN AND STUDY SAMPLE: A group of 40 participants diagnosed with Ménère's syndrome were fitted with Widex Senso Diva hearing aids and were provided with a portable Senso Programmer 3 (SP3) that allowed them to measure their own hearing thresholds at up to 14 different frequencies and to program their own devices., Intervention: The participants were instructed to test their hearing three times a day for 8 weeks and to program their hearing aids according to the measured thresholds., Data Collection and Analysis: All participants recorded some degree of hearing fluctuation during the 8-week trial., Results and Conclusions: Among participants, 70 percent continued to program their hearing aids on a regular basis and reported great satisfaction with amplification because they are now able to adjust their own devices when their hearing fluctuates.

Objective: In this study, we aimed to determine the extent to which wide dynamic range compression and compression limiting could benefit severely and profoundly hearing-impaired adults., Design: Subjects were fitted with multi-memory hearing aids incorporating frequency independent input-controlled compression with a 2:1 compression ratio and output-controlled compression limiting. The input compression threshold (CT) was varied to establish the lowest level that maintained audibility for conversational intensity speech without acoustic feedback oscillation. Where a low (40 to 57 dB SPL) CT was possible, this was compared with a moderate (65 to 74 dB SPL) level. The preferred input compression setting was subsequently compared with linear, compression-limited amplification in the same aids. In the three cases where 2:1 input compression could not be used, because of feedback or loudness insufficiency problems, compression limiting was compared with peak clipping. Field trials were conducted over a 2- or 3-mo period to establish preferences., Results: Nine of the 16 subjects preferred the inclusion of the higher level input compression, and one preferred lower level input compression. Four subjects preferred linear, compression-limited amplification, one favored peak clipping, and one could not be satisfied with any of the options provided., Conclusions: 2:1 input compression was useful, and preferred by 10 of the subjects, but for nine subjects the preferred CT was relatively high. With a group 4-frequency average loss of 87 dB HTL, the results demonstrate that fast-acting, low compression ratio systems can be useful for losses traditionally regarded as the domain of linear amplification.

Prompted by a recent paper in this journal (Snik et al., 1995), this communication compares the gain and frequency response preferred by a group of 21 severely and profoundly hearing-impaired children (37 test ears) to the NAL-RP and the DSL 3.0 hearing aid prescriptions. The results support the findings of Snik et al. (1995) that the NAL-RP procedure provides an adequate prescription of amplification on average. The individual discrepancies between prescribed and preferred characteristics imply that fine-tuning with an evaluation tool is necessary for some children. It is uncertain whether previous listening experience affects listeners' preferences, and it is suggested that further studies be carried out to address this issue.

The relationship of speech recognition to hearing threshold levels and to aided speech-peak sensation levels was examined in a group of severely and profoundly hearing-impaired adults. Closed-set vowel and consonant recognition tests were administered at the subjects' most comfortable levels. Both vowel and consonant recognition scores were relatively predictable from hearing threshold level at 2000 Hz, the correlations being -.84 and -.76, respectively. Recognition of most speech-feature contrasts was also predictable from hearing threshold levels, at one or two frequencies, always including 2000 Hz. The predictability of speech recognition was similar, but no better, from aided speech-peak sensation levels than from hearing threshold levels. Vowel and consonant scores were similar to or better than those reported in previous studies, possibly reflecting subject selection factors and/or extensive testing that was used to optimize hearing aid fittings. For the majority of subjects, altering the low-frequency response of the hearing aid did not significantly affect vowel or consonant recognition scores.

The optimal frequency response slope, from the low frequencies (250 or 500 Hz) to 2000 Hz, was estimated for each of 46 severely or profoundly hearing-impaired adults. The estimates were derived from paired comparison judgments of speech filtered to simulate different frequency response conditions, from home trials and ratings of different tone settings of high-powered, behind-the-ear hearing aids, and for 28 subjects, from speech recognition testing. The estimated optimal response, expressed as the slope from 250 to 2000 Hz and as the slope from 500 to 2000 Hz, was compared with the response prescribed by the National Acoustic Laboratories (NAL) procedure and its relationship to audiometric variables was analyzed. Insertion gain was measured for the preferred volume setting with the best frequency response. Preferred gain was typically about 10 dB higher than the NAL prescribed gain. Considering these results in relation to other data, it appears that the "half-gain" rule ceases to apply when HTL exceeds about 70 dB. The estimated optimal frequency response agreed with the NAL response for some subjects but relatively more low frequencies were required for between a third and half of the subjects, depending upon how frequency response is expressed. Generally, more low frequencies were required if HTL at 2000 Hz exceeded 95 dB, whereas the NAL response was usually appropriate for other cases.